Some university teachers of embryology welcomed Haeckel’s pictures,
but experts who disagreed with his particular approach to Darwinism accused
him of making embryos look more similar than they really are.
Haeckel was criticized fast, but the attacks took several years to
take off. The Basel zoologist Ludwig Rütimeyer raised the alarm. First,
he charged Haeckel with having figures representing different species printed
from the same block . Obviously sharp practice,
Haeckel corrected this in the second edition and eventually explained it
away as ‘extremely rash foolishness’. Second, Rütimeyer said Haeckel
had tendentiously miscopied standard illustrations.
This was much more debatable. Even as the Natural History of Creation
made Haeckel a lightning rod for Darwinist controversy, these figures had
enough competent supporters to stay through many editions.
Haeckel’s second semi-popular book, the Anthropogeny (1874),
was filled with new and provocative pictures, including a
much expanded comparative embryological
grid. Rütimeyer’s ex-colleague, Wilhelm His, who had developed a rival,
physiological embryology, which looked, not to the evolutionary past, but
to bending and folding forces in the present. He now
repeated and amplified the charges,
and lay enemies used them to discredit the most prominent Darwinist. But
Haeckel argued that his figures were schematics, not intended to be exact.
They stayed in his books and were widely copied, but still attract controversy
Haeckel’s ‘comparison of the embryos’ of various vertebrates
‘at three different stages of development’. This
expanded double plate shows fish (F), salamander (A),
turtle (T), chick (H), pig (S), cow (R), rabbit (K),
and human (M) embryos at ‘very early’ (I), ‘somewhat
later’ (II), and ‘still later’ (III) stages. It was
meant to illustrate the similarity between human embryos
and those of other vertebrates. Haeckel explained that
this is more complete at early stages and retained longer
between more closely related groups.
Lithograph by J. G. Bach of Leipzig after drawings
by Ernst Haeckel from his Anthropogenie oder Entwickelungsgeschichte
des Menschen. Gemeinverständliche wissenschaftliche
Vorträge über die Grundzüge der menschlichen Keimes-
und Stammes-Geschichte, Leipzig: Engelmann, 1874,
plates IV–V. Two plates together 23.2 x 30 cm.
Haeckel’s expanded embryological comparison,
‘The specific physiognomies of young embryos’.
The Swiss anatomist Wilhelm His deployed these figures
of a human embryo (left) and a pig embryo (right) against
Haeckel. Making great play of having drawn accurately,
His highlighted the characteristic differences that
were already apparent between the large-brained human
and the large-snouted pig. These illustrations appear
in the book with which His tried to interest a wider
audience in an approach that looked, not to the evolutionary
past, but to present-day forces that transform one developmental
stage into the next.
Wood-engravings from Wilhelm His, Unsere Körperform
und das physiologische Problem ihrer Entstehung. Briefe
an einen befreundeten Naturforscher, Leipzig: Vogel,
1874, pp. 194–5. Human embryo drawing 8.5 cm high.
Illustrations by Wilhelm His to show
‘the specific physiognomies of young embryos’, 1874